The present invention relates to a plastic compensating reservoir for hydraulic brake systems, such as brake systems of automotive vehicles. The reservoir has two interconnected brake fluid chambers, each of which is in communication with a port to connect each fluid chamber to a pressure chamber of a tandem master brake cylinder.
A generally similar compensating reservoir is known from British patent specification No. 1,548,669. The reservoir of this patent comprises two brake fluid chambers arranged at a distance side by side and interconnected by an intermediate chamber disposed between them. The intermediate chamber contains a float of a fluid level indicator. Each of the brake fluid chambers at its top is closed by a separate cap and each has at its bottom a port, with both ports extending in parallel to the vertical axis of the reservoir. Due to its complicated design, the reservoir shown by the patent is very expensive to manufacture, since it cannot be made by injection molding. Further, this reservoir requires a relatively large mounting space.
Admittedly, there are other known plastic compensating reservoirs which can be manufactured by injection molding. These moldable compensating reservoirs, however, are likewise relatively complicated in their design and contain several undercuts. For such reservoirs, the lower part and the upper part must be injectionmolded separately during manufacture and welded together subsequently. Consequently, this procedure requires considerable time and expense, since a casting machine will be occupied twice followed by a welding process afterwards.